Are 120 / 140 FHC seats the same other than possibly the tunnel cover ?
The amount of pleats seems to differ on the base . Your 120 have 11 and the 140 has 9
According to Porter’s “Original Jaguar XK” (2003 edition p.51) on the 140: “The seats were very similar, with most dimensions and materials unchanged from the 120, but the size of the steel seat pan and plywood base were different. The backrests on the coupes were thinner to give more room in the back. The seat base frames and cushions were common to all models, apart from additional metal strengthening for the seat frames on later coupes.” On the 120, you are right, the seat cushions have 10 pleats and the 140 have 9. While the seat backs are appreciably thinner on the 140 they are also virtually flat across without the compound curves seen on the 120.
discounting alloy 120 seats and the cutout of the back of seat on roadster there are 2 types of XK120 seats.
The bucket seat and the split bench
the bucket seat has quite a contour in the back
the split bench is literally flat and as per name designed I see it as to let someone sit in the middle!
from what I can see of the 4 pics of are a late set of bucket seats from 120FHC/DHC but would need to see pic of either end of the upright to totally determine.
There are multiple difference in 140 seats the cushion is 1 inch narrower the back whilst similar width has different height and metal frames that form the hinges then there are 2-3 version of the early version of seat and then there is the late seat built on a metal tubular frame as per 150 construction this type was not available on the roadster.
I will come back and add some pics and further info
Just to be clear, the term bucket confused me as in the USA that term means individual seats totally separated from each other, such as in an E-Type.
The '53 XK120 FHC seats pictured above are what I would call sculptured backs. I think that’s what you meant by bucket. They span over the driveshaft tunnel and sort of meet in the middle. It would be uncomfortable on the spine for a middle passenger.
The seats in my '51 120 FHC are pretty much the same, though they don’t have that big air vent hole in the bottom pan.
I agree the most if not all people would consider buckets seat as 2 completely separate seats ie TR3 E type etc I took bucket as being the shape to support the driver and even if they touch they are individually supporting the driver and passenger
An SS MKIV and V have “individual seats” but one might not describe them as bucket.
The MKI did have bucket seats in the manual cars and split bench in the auto
A bucket seat is a car seat contoured to hold one person, distinct from a flat bench seat designed to fit multiple people. In its simplest form it is a rounded seat for one person with high sides, but may have curved sides that partially enclose and support the body in high-performance automobiles.
Bucket seats first appeared after World War II, making their debut in small European cars with floor-mounted shifter and parking brake lever. They are typically standard in front in fast cars to keep drivers and other passengers in place when turning at speed. Rear “bucket seats” are typically hybrids of bench and true bucket seats, being contoured generally like the latter but fixed in place, even when divided by a center console, and thus lacking a free-standing bucket seat’s front-rear and backrest angle adjustability